Suspension for lighting fixtures



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I. WOLARSKY Filed June 15, '1937 INVENTOR JS/D ces I/OAPJKY SUSPENSIONFOR LIGHTING FIXTURES Oct. 8, 1940.

Patented Oct. 8, 1940 UNITED sTATEs PATENT OFFICE 7 Claims.

The present invention relates to suspensions for lighting fixtures, andis more particularly directed toward adjustable suspension, whereby themounting height of the fixtures may be ad justed.

The present invention contemplates a. form of adjustable suspensionwhich is readily usable with various forms and styles of suspendedlighting fixtures, such as occur in school, industrial and officelighting. In this eld there is no standard length of support orsuspension for the xture. These lengths depend upon ceiling height andother factors which must be taken into account, so that it is difficultfor manufacturers to provide their jobbers and dealers with a stock offixtures which can be readily adapted for mounting in various locations,especially where stem type suspensions are demanded.

According to the present invention it is not necessary to resort tochain suspension to provide a readily adjustable suspension for thexture, and it is possible for the dealer or jobber to have a stock ofsuspensions on hand which will fit practically any situation which mayarise.

According to the present invention the suspenf sion contemplates theemployment of two tubular telescoping members, one secured to thefixture supported at the ceiling, and the other to the fixture body, andthat one of these members should be provided with suitablemeans foradjustably connecting it with the other in such a way that the overalllength of the suspension may be adjusted and preferably so that Vtherewill be no turning or twisting ofthe parts, whereby twisting of fixturewires is avoided.

The accompanying drawing, shows, for purposes of illustrating thepresent invention, several embodiments in which the invention may takeform, it being understood that the drawing is illustrative of theinvention rather than limiting the same.

In the accompanying drawing,

Figure l is a diagrammatic elevational view illustrating a lightingfixture suspension; y

Figure 2 is a vertical sectional viewthrough the same with parts inelevation;

Figure 3 is a vertical sectional view with parts in slightlydiierentposition than in Figure Zand taken on the line 3-3 of Figure 4;

Figure 4 is a transverse sectional view on the line 4-4 of Figure 3;

Figures 5 and 6 are fragmentary elevated sec* tional views illustratingmodified forms of construction; and

Figure 7 is a view similar to Figure 2, showing end of thisv tubularmember I5 is threaded, as

indicated at I6,-to receive a bushing I'I.

This bushing is preferably locked in place by an indentation, indicatedat I8. The bushing has a key like member I9, which extends into a keyway29 formed in the side .wall of a tubular stern 2l. This stem is providedwith running threads extending its entire length, as indicated,

and at the upper end the stem carries an abutmentin the form of a nut22, which prevents removal of the stem downwardly. This stem is adaptedto telescope inside the tubular member I5, and at its lower end isfixedly connected to the fixture body. v

In the form here shown the lower end 23 of this stem is threaded into aring 24, and is secured to the cap 25 of a lamp socket. The ring 24 islocked against rotation by a pin, indicated in dotted lines at 26. Thering 24 supports a bail'or yoke 2'I adapted to support the glassware ofthe fixture, and a socket cover, indicated at 28, covers the parts.

Owing to the fact that the socket 25 is securely attached to the lowerend of the tube 2l and to the secure attachment customarily employedbetween fixture stems and canopies it is possible to secure anadjustment ofthe xture body relative to .the socket by merely turningthe fixture body and nut 24 on the tube 2I to raise thexture bodyrelative to the socket. In this way the glassware can be adjustedrelative to the socket after the wiring has been completed and withoutdisturbing the wiring in any Way.

The threaded stem 2| carries a nut 29 which can be adjusted along thestem, and this nut is f threaded at 30, as indicated in Figure 3, so asto thread into the threads carried in the bushing Il. An externalcovering sheath 3l is provided to conceal the threads on the stem 2| andnut,r

and this sheath' assumes the position shown in Figure 2 when the fixtureis hanging. It can be elevated up to the dot-and-dash line position ofFigure 1, or to the full line position of Figure 3 to afford access tothe nut for effecting adjustment of the overall length of thesuspension.

The bottom of the keyway 20 may be provided with punch marks or otherindications, such as xs indicated at 32, so as to indicate to theelectrician the adjustment which is being effected. This makes itpossible to readily adjust a number of fixture stems to a uniform lengthwithout measuring them.

In the arrangement shown in Figure 5, the bushing Il is provided with apin I9 instead of a bent over portion, as indicated in Figure 3. Theparts are otherwise the same.

In the arrangement shown in Figure 6, the lower end of the tubularmember l5' is reduced in diameter, as shown at I6', and internallythreaded so as to co-operate with the the nut 29.

The key like member I9" is provided by striking in a portion of the tubel5.

In the arrangement shown in Figure 7, the suspension for the fixture issecured to an element, indicated at 40. This may be of any desired formof construction. It isV here shown as internally threaded to support theupper end of theitubular stem 4 I, and this is locked in place by a locknut, indicated at 42. This tubular stem is provided with running threadsits entire length, as shown, and with a keyway indicated at 43. The stem4| carries a nut 44, similar to the nut 29, an'd adapted to be threadedinto a bushing 45, as shown in Figure 3. This bushing d5 is threadedinto a tubular member 46, the lower end 41 of which is secured to thesocket 48 in any convenient manner, for example, by the member 49. Astop member 50 carried by the stem 4l prevents accidental separation ofthe parts. The external cover sheath is shown at 5I, and it is suitablysecured to the support 40, for example, by the threads indicated at 52.

From the foregoing it will` be apparent that a very convenient form ofadjustable suspension for lighting fixtures has been provided. Itconsists of inexpensive screw machine made parts which can be veryeasily assembled. The concealed parts can be made out of inexpensivematerials, so that the cost of the suspension is moderate.

It is only necessary to make up suspensions intwo sizes to be able toadapt the suspension for practically the entire range of suspensionlengths employed in commerciallighting iixtures. For example, onesuspension may be adjustable between the lengths of 18 and 34 inches,and another one adjustable between the lengths of 36 and 70 inches.

It is obvious that the invention may be em'- bodied in many forms andconstructions within the scope of the claims and I wish it to beunderstood vthat the particular forms shown are but a few of the manyforms. Various modications and changes being possible, I do nototherwise limit myself in any way with respectthereto.

What is claimed is:

l. A device for suspending the body of an electric lighting xture from aceiling support cornprising two telescoping tubular members one securedat its upper end to the support so as to hang down from the supportforits entire length, the other member being substantially the same lengthas the rst and secured at its lower end to the fixture body so thatwiring may be carried from the ceiling support to the fixture body, thesmaller diameter member being provided with a running thread and akeyway both extending from said secured end thereof nearly to the otherend, a nut threaded on said smaller diameter member, the larger diametertubular member carrying a projection which enters' the keyway wherebythe tubular members are non-rotatably connected together for slidingmovement so that their overall length may be adjusted from substantiallythe length of one tubular element to substantially twice that length,the nut being adjustable along the smaller diameter member so as to beopposite the fr ee end ofV the larger diameter member at any length towhich the suspension device may be extended, and means fordisconnectably coupling the nut and free end of the larger diametermember.

2. A.. device such as claimed in claim 1, wherein the projection iscarried on a bushing secured in the ,outer tubular member, and thebushing and nut have co-operable threads.

3. A device such as claimed in claim 1, wherein the free end of thethreaded member has a stopv which engages the projection and preventsthe withdrawal of said member from the outer member so that the fixturebody may be supported when the nut is disconnected from the tubularmember.

4. A device such as claimed in claim 1, having an outer sleeve slidableon the outer tubular member and of a length to conceal the threadedmember, the nut and adjacent end of the said outer tubular member at anylength to which the suspension device may be extended, and to be movedto provide access to the nut.

5. A device such as claimed in claim 1, wherein the large diametermember is indented to form the key and has a threaded end to cooperatewith threads on the nut.

6. A device such as claimed in claim 1, wherein the large diametermember is secured at its upper end tov the ceiling support and the lowerend of the threaded member is secured to the xture body.

'7. A device for suspending the socket and globe support of an electriclighting xture from a ceiling support comprising two telescoping tubularmembers, the larger diameter member being secured at its upper end tothe support so as to hangdown from the support for its entire length,the other member being substantially the same length as the first andprovided with a running thread and a keyway both extending from adjacentthe upper end to the lower end thereof, the said lower end beingindependently threadedly secured to the socket and globe support so thatwiring may be carried from the ceiling support to the socket, a nutthreaded on said smaller diameter member above the globe support, theupper tubular member carrying a projection which enters the keywaywhereby the tubular members are non-rotatably connected together forsliding movement so that their overall length may be adjusted fromsubstantially the length of one tubular element to substantially twicethat length, the nut being adjustable along the smaller diameter memberso as to be opposite the free end of the larger diameter member at anylength to which the suspension device may be extended, and means fordisconnectably coupling the nut and free end of the larger diametermember.

IsIvDoRE WoLARsKY.

